I added that stuff to my engine about a month ago.
I had some ticking and a small chirping sound. I had adjusted the valves in the Spring and I thought I did a good job. I added the Rislone ZDDP stuff to see if that helped. Nope - it did not work - no change - no easy fix. So, the valve cover came off again. Using a 2.5 ft long piece of wooden dowelling as a stethoscope I was able to determine three valves needed adjusting. After adjusting the valves, it still had the chirp, so while the valve cover was off I squirted some oil on the rockers and it quieted down. The chirp hasn't returned even after the truck got a pretty good work Saturday night.
So, I suggest you check your valve adjustment.
